October 11, 2013
Rosetta To Begin Comet Chase Upon Its Awakening In 100 Days
[ Watch the Video: Rosetta’s Twelve-Year Journey in Space ]
Lee Rannals for redOrbit.com - Your Universe Online
The European Space Agency's (ESA) Rosetta mission will be arising from hibernation in about 100 days to make a long-awaited approach of a destination mission controllers have been aiming for for the past decade.
The Rosetta mission has been traveling through space since March 2, 2004 towards comet 67P/Churyumov–Gerasimenko. During its travels, the spacecraft has flown past Earth three times, once past Mars and has imaged two asteroids.
ESA put Rosetta to sleep in July 2011, a year after taking an image of the asteroid Lutetia. The spacecraft was placed in hibernation during the coldest, most distant leg of the journey as it traveled about 500 million miles from the Sun -- in the neighborhood of Jupiter. Rosetta was oriented during this time so that its solar wings faced the Sun to receive as much energy as possible.
Rosetta's alarm clock for the last leg of its decade-long journey is set for January 20, 2014. Once the spacecraft wakes up it will warm up its navigation instruments and then will stop spinning so it can point its main antenna at Earth.
“We don’t know exactly at what time Rosetta will make first contact with Earth, but we don’t expect it to be before about 17:45 GMT on the same day,” Fred Jansen, ESA’s Rosetta mission manager, said in a statement.
Rosetta will still be about 5.5 million miles away from its destination when it awakens, but while it moves closer toward the comet 11 instruments on the orbiter and 10 on the lander will be turned on and checked. Towards the end of May Rosetta will be executing a major maneuver to line up for rendezvous with the comet in August.
ESA said it expects to receive the first images of 67P/Churyumov–Gerasimenko in May, which will help scientists improve calculations of the comet's position and orbit. As it nears its destination, Rosetta will be taking thousands of images to provide further details about the comet's major landmarks, its rotation speed and spin axis orientation.
Rosetta will perform extensive mapping of the comet's surface during August and September, after which ESA will be choosing a landing site for the Philae probe. This will be the first time a space agency has landed on a comet.
ESA said that Philae will be using a series of screws and harpoons to stop it from rebounding back into space as it lands. The probe will be sending back a panorama of its surroundings and very high-resolution pictures of the surface and will perform on-the-spot analysis of the composition of the ice and organic material.
Philae will be using an instrument to drill 8 to 12 inches below the surface. After this it will be able to sample material of the comet's surface and send it back to its onboard laboratory, similar to NASA's Curiosity rover on Mars.
“The focus of the mission then moves towards what we call the ‘escort’ phase, whereby Rosetta will stay alongside the comet as it moves closer to the Sun,” said Jansen.
Rosetta will be monitoring the comet as it approaches the Sun, watching the changing conditions on the surface of the comet as it warms up and its ice sublimates.
“This unique science period will reveal the dynamic evolution of the nucleus as never seen before, allowing us to build up a thorough description of all aspects of the comet, its local environment and revealing how it changes even on a daily basis,” Matt Taylor, ESA’s Rosetta project scientist, said in a statement. “For the first time we will be able to analyze a comet over an extended period of time – it is not just a flyby. This will give us a unique insight into how a comet ‘works’ and ultimately help us to decipher the role of comets in the formation of the Solar System."